a) In the following algorithm, the Algorithm Algo4(r) parameter r is the root of a binary if r is a leaf then r tree.... What does Algo4 do? return 0 else return 1+A1g04(left child of r)+Alg04(right child of r) c) The path length of a tree T is the sum of the depths of all the nodes in T. Assume that the depth of any node in T is not known beforehand. Describe an algorithm in pseudo- code for computing the path length of a tree T (which is not necessarily binary)